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warrbuk
01-03-2016, 12:36 PM
Hello,

I was looking at a model 12 FCV in 223 to shoot ground squirrels with. I noticed that the 223's all came with the 9 twist. I have a large supple (20k) of 50 grain V-Max, and TNT's on hand and was wondering what type of accuracy to expect with those bullets?

Thanks
Mark

scope eye
01-03-2016, 12:40 PM
I don't see any reason why you can't shoot them, if for any reason they start coming apart just slow them down a little. I highly doubt you will have that problem. I have an AI version in 9 twist and it's all good.

Dean

darkker
01-03-2016, 12:59 PM
The TNT's may well come unglued unless you slow down.
Remember that your specific barrel smoothness will play a very large part in the absolute numbers. I did this posting 3 years ago. The AMP jacket that Hornady now uses may or may not change things. Also now that Speer out from under those Bas$%rds at ATK, they are furiously working on several things. They are currently pressure testing a brand new manual, and working on several new bullets. Stay tuned, should see something from them later this year.

The math:
MV * 720 / Twist = RPM

The RPM limits, as told to me by the Manufacturers:

Dogtown bullets:
@ 260,000 RPM - Nosler made

Varmint Nightmare bullets:
@ 260,000 RPM - This is based off of my personal reloading experiences with them. 99% sure these are the same as Dogtowns.

Speer TNT's (low velocity):
@ 240,000 RPM - Based off of info in their loading manuals, and personal experiences. When I have talked to Speer on the phone(last time was a month ago) The people that take "technical" questions really do seem to be clueless, and not particularly helpful with this info.

Hornady V-max & SP's:
@ 290,000 RPM - Hornady told me last week that the V-max bullets, and SP's have the same rating. While I'm not as big of a fan of them as of late, they are quite helpful on the phone in this arena.

Hornady SXSP:
@ 240,000-260,000 RPM - One of my children drew me a lovely picture, over my notes; so this figure is difficult to make-outhttps://www.shootersforum.com/images/smilies/wink.gif

Sierra Varminter:
@ 216,000 RPM - The Sierra tech "didn't have his calc sheet in front of him". But told me that the velocity limit was 3600 FPS in a 12 twist barrel.

Sierra BlitzKing:
@ 352,000 RPM - Same tech as above, claimed the ceiling is 4400 FPS from a 9 twist barrel.

Nosler's BT are the same as the Blitzking.

kkeene
01-03-2016, 02:32 PM
I've not had any problem with the various 50 gr bullets in my 223, and get good accuracy (typically 1/2 MOA at 100 yds for the v-max and 3/4 MOA for the TNT's).

However, I get even better accuracy with the 52 gr HPBT match 1410 Sierra's.

warrbuk
01-04-2016, 12:39 AM
Thanks for the info! Darkker you went above and beyond.

I will likely give a 9 twist a try.

Thanks
MW

LHitchcox
01-04-2016, 09:03 AM
I shoot 50 grain V Max is an AR 15 with 1 in 9 twist. The accuracy is better than I had even hoped for. Normally a 5 shot group from the Oracle upper is around .75 inch CTC. That is with hand loads using TAC.

Aamity
01-16-2016, 03:06 AM
My FCP-k .223 shoots very well with 55gr at 3240fps and 62gr at 3100 fps out to 400 plus yards. I haven't tried anything heavier than 62gr fmj. I would think it would shoot lighter bullets just fine.

Smokey262
01-16-2016, 08:03 AM
now that Speer out from under those Bas$%rds at ATK, they are furiously working on several things. They are currently pressure testing a brand new manual, and working on several new bullets. Stay tuned, should see something from them later this year.

I am curious how you discovered that some folks at Speer were not fond of being owned by ATK, and that they are now doing work on new products, including a manual?

It does seem like awhile since they have done either